Muft Shiksha
Update

Muft Shiksha™ एक 100% Free Education Portal है 🇮🇳, जिसका उद्देश्य Class 9–12 के हर विद्यार्थी तक High-Quality Education को पूरी तरह मुफ्त पहुँचाना है। 🇮🇳 हम मानते हैं कि अच्छी शिक्षा किसी student की आर्थिक स्थिति पर निर्भर नहीं होनी चाहिए। 🇮🇳 हर विद्यार्थी को वही Quality Study Material, MCQs, Quizzes, Exam Preparation, Concept-Based Learning और Bilingual Support मिलना चाहिए, जो आमतौर पर महंगी Coaching या Premium Platforms में मिलता है। Muft Shiksha™ 🇮🇳 इसी सोच के साथ बनाया गया है

Subjects

Science

Chemical Reactions and Equations

रासायनिक अभिक्रियाएँ और समीकरण

In Class 10 Science, under the chapter Chemical Substances – Nature and Behaviour, this topic introduces chemical reactions as changes that form new substances. Students learn to identify reactants and products, represent reactions through word and chemical equations, and write balanced equations using correct chemical formulae while following the law of conservation of mass.

Practice questions

When can an upward arrow be used in a chemical equation?When is a downward arrow used in a chemical equation?Which of the following is only a physical change?A student did not clean a magnesium ribbon before burning it, so it appeared to burn slowly. What is the main purpose of cleaning the ribbon?A student adds zinc granules to a blue copper sulfate solution. After some time, the blue colour fades and a reddish-brown coating appears on the zinc. Which conclusion is correct?Which of the following examples involves a change in properties and the formation of a new substance?If the total mass in a closed container after a chemical reaction remains equal to the total mass before the reaction, which law does this illustrate?Which statement best identifies a chemical reaction?In an unknown reaction, an insoluble white solid forms, but no noticeable temperature change is observed. What is the most appropriate conclusion?A student burnt a magnesium ribbon in air and obtained a white powder. Which is the correct conclusion about the powder and the reaction?If two reactants combine to form only one product and heat is released, what is the correct classification of the reaction?When water is added to calcium oxide, the container becomes hot. Which conclusion is correct from this observation?What is the correct volume ratio of gases in electrolysis of water?During the electrolysis of water, which gas is produced at the cathode in a greater volume?A brown gas is released on heating lead nitrate. Which gas is it?Which solid product is formed on thermal decomposition of lead nitrate?Why does silver chloride turn grey when kept in sunlight?Why is silver bromide stored in a dark-coloured bottle?Which statement is correct when an iron nail is placed in copper sulphate solution?When an iron nail is placed in copper sulphate solution, the reddish-brown coating formed on the nail is of which substance?